During operation of vehicles that include multi-cylinder internal combustion engines, operating conditions or driving situations exist in which the required power may be provided by less than all of the cylinders. For that reason, individual cylinders or cylinder groups may be deactivated in such operating conditions for increasing efficiency. The deactivation of one or multiple cylinders makes it possible to operate the cylinder or cylinders, which continue to be active, at increased power and better efficiency. The operation using only a portion of the cylinders is also denoted as partial engine operation, and the term “partial engine operating phases” will be used in the following for operating phases of an internal combustion engine of this type. Usually, half of the cylinders are shut off, which is denoted as half-engine operation (HMB). If all cylinders are active, this is the so-called full engine operation (VMB).
The engine controls of modern vehicles are equipped with so-called E-GAS systems (electronic accelerator pedal). In this case, there is no longer a mechanical connection between the accelerator pedal and the engine actuator, such as the throttle valve in gasoline engines or the control lever in diesel engines, but instead the engine actuators are activated electronically. For safety reasons, so-called E-GAS monitoring is implemented in this case, which detects potentially torque-increasing errors, and then transitions the vehicle into a safe operating condition.
The safe operating condition is usually characterized by a so-called safety fuel cut-off (SKA), which ordinarily takes effect at a limiting speed (of, for example, 1500 RPM−1), and a reduced fuel metering below the limiting speed.
If the internal combustion engine is operated in partial engine operation, the potentially torque-increasing errors, which must be monitored, include whether the unneeded cylinders are shut off. This may be accomplished by checking the ignition and injection suppression mask for the pattern typical for the cylinder shutoff. If a torque-increasing error is detected in this case, the E-GAS monitoring responds and activates the safety fuel cut-off.